Saturday, March 17, 2018

Spring Peeper Babies

Tadpole emerges left upper, intact egg with tadpole to the right - Linda Bower
Linda Bower just sent me this incredible video of spring peeper tadpoles emerging from their eggs so I decided to update a previous blog on the little mighty mouths.  We first started hearing the chorus four weeks ago.  According to Animal Diversity Web:
The species is one of the first anurans to begin breeding after winter hibernation. The breeding period lasts from March - June, when 800 - 1000 eggs per female are laid in shallow ponds. The eggs hatch within 6 to 12 days, and tadpoles transform to adults during July (range 45 - 90 days).
"The species is one of the first anurans to begin breeding after winter hibernation. The breeding period lasts from March - June, when 800 - 1000 eggs per female are laid in shallow ponds. The eggs hatch within 6 to 12 days, and tadpoles transform to adults during July (range 45 - 90 days)."
The species is one of the first anurans to begin breeding after winter hibernation. The breeding period lasts from March - June, when 800 - 1000 eggs per female are laid in shallow ponds. The eggs hatch within 6 to 12 days, and tadpoles transform to adults during July (range 45 - 90 days).
The species is one of the first anurans to begin breeding after winter hibernation. The breeding period lasts from March - June, when 800 - 1000 eggs per female are laid in shallow ponds. The eggs hatch within 6 to 12 days, and tadpoles transform to adults during July (range 45 - 90 days).
Most of these eggs won't survive to produce adult peepers or we would likely be deafened by the songs.  Frog eggs and tadpoles are at the bottom of the aquatic food chain, eaten by any denizen of the shallows that can get its mouth around them.  Linda captured one of those attempts in this video of a dragonfly nymph attacking a peeper egg just before it could hatch.

Dragonfly nymph attacking peeper egg with tadpole inside - LB
This time of year the sound of spring peepers (Pseudacris crucifer) rings across the valley from a nearby pond.  They spend the winter in torpor, hiding in leaves and under logs.  So how do these apparently soft and tender amphibians survive the winter? 

"The spring peeper produces glucose, or sugar, and "freezes" itself for the winter. In winter, peepers' bodies freeze--but their cells don't rupture because of the concentrated sugars in them. These sugars act as a kind of natural anti-freeze.
Like many of the chorus frogs, the spring peeper is often heard, but not seen. It gets its name from its call, which consists of a single clear note or peep, occurring once a second. Only the males sing, calling from shrubs and trees standing in or overhanging water.
The faster and louder a male sings, the more likely he is to attract a mate. A male peeper may also give a lower-pitched trilled whistle, usually when another male has moved too close to its calling site. During the daytime, peepers often call during light rains or in cloudy weather."  Maryland DNR
X marks the frog - REK
Peepers are hard see, let alone to photograph as they are watching for anything moving above them  At less than 1.5" almost everything is higher.  They have great camouflage, with a faint "X" on the back as their distinguishing mark, the reason for the name P. crucifer (crucifer = “cross-bearer”).  Because of the cacophonous chorus, it is hard to localize an individual frog.


A few years ago I chose a pond with a six foot high dam so I could approach the water unseen.  The chorus was in full voice by 4:45pm while the low lying sun was still reaching the pond surface.  I crawled up the side on my belly like Uncle Sam taught me in Vietnam, discovering in the process that my belly wasn't the same one I had used in 1967.

I reached the top and peered over and saw....nothing!  There was the water, dead leaves and floating sticks with even a few mushrooms, but no frogs.  The cacophony continued unabated, scattered voices from all around the pond edges.  Finally I made out a tiny bump that seemed to vibrate on a log to my left. 

Crawling six feet to the left and then peeking over the edge I was face to face with a singing peeper.  He (only males call) watched me closely as I ever so slowly brought out my pocket camera.  I waited several minutes with my arms outstretched until he again joined the chorus.  The next 10 minutes I continued to film it, pausing when it became suspicious and stopped singing.  Mission accomplished with this video!

A final confession.  I broke the rule of "Take nothing but pictures leave nothing but footprints, kill nothing but time."  When I got home I discovered I had taken a number of ticks from the pond dam. You can guess the killing part.
===
Speaking of mating calls, here is some research into how birds modify their songs when loud noise pollution makes finding mates difficult.

No comments:

Post a Comment